JPH03154403A - Waveguide device - Google Patents

Abstract

PURPOSE:To eliminate the need for removing a main body from an adjustment jig by turning an adjustment screw placed to a waveguide at a proper position from a position of an antenna terminal so as to adjust the conversion loss. CONSTITUTION:An adjustment screw 15 to optimize the conversion loss is fitted to a waveguide at a position by a prescribed size 16 deviated from an antenna terminal 7. Moreover, the diameter of the adjustment screw is selected larger than the diameter of the antenna terminal and a thread hole 17 for the adjustment screw is made to the waveguide 1. Then the conversion loss is adjusted by turning a thread head of the adjustment screw exposed to the outside of the waveguide device thereby moving the tip of the screw in the waveguide vertically. Thus, the adjustment is implemented at the outside of the waveguide and a BS converter is adjusted without need of removing it from the adjustment jig.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides a mode exchanger between a waveguide and a microstrip line of a microwave integrated circuit in an outdoor apparatus for receiving satellite broadcasting (hereinafter referred to as a BS converter). This invention relates to a waveguide device equipped with an adjustment mechanism.

Conventional technology Conventionally, this type of waveguide device was used as an outdoor device for receiving satellite broadcasting (
The configuration shown in FIG. 3 was based on the BS converter block diagram shown in FIG. 2 (hereinafter referred to as BS converter).

In FIG. 2, a radio wave transmitted from a broadcasting satellite is bisonally modulated by a primary radiator, passes through a circular-to-linear polarization converter, and enters a waveguide.

The electromagnetic waves propagating in the waveguide 21 are converted into electrical signals by the mode converter 22, and amplified by the high frequency amplification circuit 25 of the microwave integrated circuit 24 via the air router 23.
The local excavation signal of the local oscillator circuit 26 is heterodyne detected by the mixing circuit 2a to obtain a primary IF signal, which is amplified by the intermediate frequency amplification circuit 28 and sent to an indoor device (not shown) as an output signal of the BS converter. BS tuner (not shown). In addition, in the figure, 29 is a primary radiator, and 30 is a power supply circuit.

Among the above BS converter block configurations, the configuration of a waveguide device that performs mode exchange in a waveguide is shown as an assembled sectional view in FIG.

FIG. 3 shows an electric field coupling type waveguide device. Reference numeral 1 denotes a waveguide, which is composed of a rectangular surface 2 of mm×B and a shielding surface 3 located at an appropriate distance from the opening. Reference numeral 4 denotes an antenna terminal, which is placed at a predetermined position from the shielding surface of the waveguide and converts electromagnetic waves into electrical signals.

The antenna terminal is formed using a thin plate material such as a brass plate, and the electrical signal converted by the antenna terminal is transmitted to the microwave integrated circuit 6.

In this method, in order to minimize conversion loss from electromagnetic waves to electrical signals, the tip of the antenna terminal is tilted in the direction of arrow 6 and adjusted to the optimum position while being deformed.

Problems to be Solved by the Invention In this conventional method, ■ In the adjustment work to minimize conversion loss, the adjustment of the antenna terminal is performed from the opening of the waveguide, so simultaneous measurement of conversion loss is not possible. .

Therefore, after installing the BS converter in the adjustment jig and measuring the loss level, it is necessary to adjust the antenna terminal by guessing, then install it in the adjustment jig again, and measure the loss level. Adjustments may need to be redone, which takes time and increases man-hours.

■ Adjustment of antenna terminals using thin plate material involves tilting and deforming the antenna terminal, so the elasticity of the material, that is, springback, causes the antenna terminal to return slightly to its original position from the estimated adjusted position. It becomes increasingly difficult to make adjustments.

■ It is necessary to install the microwave integrated circuit board above the waveguide, and it is difficult to control the dimensions in the direction of the waveguide.

There was a drawback.

The present invention solves the above-mentioned problems. (1) To facilitate the adjustment work to minimize conversion loss and reduce the number of adjustment steps required to find the optimum point.

■ The BS converter installed in the center of the parabolic antenna partially blocks radio waves from the satellite, so as the diameter of the parabolic antenna becomes smaller due to lower costs and reduced installation costs, the BS converter also becomes smaller. is required,
Therefore, make it thin.

It is an object.

Means for Solving the Problems In order to solve this problem, the present invention is a rectangular waveguide having a structure in which one surface is open and the other surface is vertically closed with a conductor, and the waveguide is An L-shaped antenna terminal is attached near the center of the shielding surface from inside the waveguide to a shielding surface that is blocked perpendicularly to the tube, and the terminal is inserted into the through hole of the shielding surface. is characterized in that it is a coaxial line, and that a conductor rod is protruded from the tip of the bent-shaped antenna terminal in the waveguide at a position slightly eccentric from the center axis of the antenna terminal on the opposing surface. It is a waveguide device, and ■ By installing a screw on the conductor rod protruding into the waveguide at a position slightly eccentric from the central axis of the antenna terminal, and changing the protruding length by rotating the screw. This is to adjust the minimum conversion loss.

Operation The present invention has the above-described configuration.■ Adjustment of conversion loss is performed by rotating an adjustment screw installed in the waveguide at an appropriate position from the antenna terminal position, so adjustment can be done outside the waveguide. There is no need to remove the main body from the jig.

■ Adjustments can be made by simply adding screws as off-the-shelf parts.

■ By bending the antenna terminal into an L-shape, it became possible to install the microwave integrated circuit board behind the waveguide.

Example An embodiment of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a sectional view of a waveguide device of a BS converter according to an embodiment of the present invention. In FIG. 1, a waveguide 1 is composed of a rectangular surface 2 of AXB and a shielding surface 3 located at an appropriate distance from the opening. As shown in the figure, the shielding surface 3 has an appropriate dimension l from the center and a diameter at an eccentric position.
04, which has a two-stage circular hole, is the antenna terminal.The material used is brass, which has good conductivity, and is plated with gold to lower the skin resistance. The shape is such that a rod with a thick diameter part 6 and a thin part 602 is bent into an L shape with an appropriate dimension 8 of the thick part. Part 7 of the antenna terminal is placed at a predetermined position in the waveguide, and is a part that converts electromagnetic waves into electrical signals. Part 6 is a part for transmitting the converted electrical signal to the substrate 9, and is configured as a coaxial line with respect to the hole 14 in order to achieve impedance matching.

Further, the stepped portion 1o positions the antenna terminal at a predetermined position in the waveguide.

Reference numeral 11 denotes a spacer made of polypropylene, which has good moldability and a low dielectric constant. The spacer is constructed by press-fitting the antenna terminal into the circular hole 12 of the spacer and inserting it into the circular hole 13 of the shielding surface 2 of the waveguide described above.
It has the function of positioning the 6 part of the antenna terminal at the center of the antenna terminal 4 and also suppressing the rotation of the antenna terminal by press-fitting. Thirteen of the second-stage holes 13 and 14 on the shielding surface form a coaxial system with a diimpedance of 60Ω with the six antenna terminals and the spacer 11, and the circular hole 14 forms a coaxial system with the six antenna terminals and the spacer 11. A coaxial system with an impedance of 50Ω is formed. Reference numeral 16 is an adjustment screw for optimizing the conversion loss, and is attached to the waveguide so as to be positioned at a predetermined dimension 16 offset from the antenna terminal 7. The diameter of this adjustment screw is thicker than the diameter of the antenna terminal. The waveguide 1 has a screw hole 17 for this adjustment screw. The conversion loss is adjusted by rotating the screw head exposed on the outside of the adjustment screw device and moving the tip of the screw inside the waveguide up and down. After adjusting the loss with a lock nut, 18 locks the adjustment screw by rotating it after adjustment to prevent the setting of the adjustment screw from shifting due to vibration or the like. Further, in order to keep the inside of the waveguide waterproof, a circular projection 19 is provided in the waveguide centering around the screw hole 17, and the inside thereof is filled with 2° of adhesive.

Effects of the Invention As described above, the present invention provides a method for finding the best point for conversion loss when converting electromagnetic waves from a broadcasting satellite into electrical signals using adjustment screws installed at appropriate positions from the antenna terminal. Since adjustment can be performed outside the waveguide, adjustment can be made without removing the BS converter from the adjustment jig, reducing preparation time and improving productivity.

In addition, since screws are used for adjustment parts, processing is easy, and with this structure, the board can be positioned behind the waveguide, reducing the vertical dimension. The shape can be made smaller.

[Brief explanation of the drawing]

Fig. 1 is an assembled sectional view of an antenna terminal and conversion loss adjustment mechanism in a waveguide device according to an embodiment of the present invention, Fig. 2 is a block diagram of a BS converter, and Fig. 3 is an assembled sectional view of a conventional example. be. 1... Waveguide, 4, 1o... Antenna terminal.

Claims (2)

[Claims] (1) A rectangular waveguide having a structure in which one surface is open and the other surface is vertically blocked by a conductor, and the waveguide is An L-shaped antenna terminal is attached near the center of the shielding surface from the inside of the tube, and the terminal inserted into the through hole of the shielding surface is a coaxial line, and the tip of the L-shaped antenna terminal inside the waveguide is attached. A waveguide device characterized in that a conductor rod is protruded from a surface facing the antenna terminal at a position slightly eccentric from the central axis of the antenna terminal. (2) A screw is installed on the conductor rod protruding into the waveguide at a position slightly eccentric from the central axis of the antenna terminal, and the length of the protrusion is changed by rotating the screw, thereby adjusting to the minimum conversion loss. The waveguide device according to claim 1.